typodupeerror

## Around the World in a Solar Plane153

Coati writes "Bertrand Piccard, the guy that flew around the world in a balloon, wants to do it again, this time in a solar plane."
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## Around the World in a Solar Plane

• #### Sunny skies (Score:4, Funny)

on Friday November 28, 2003 @10:08AM (#7582033)
Guess he won't be flying at night.....
• #### Re:Sunny skies (Score:5, Funny)

on Friday November 28, 2003 @10:19AM (#7582113)
Guess he won't be flying at night.....

As long as he can design a solar plane which can fly at mach 2, this shouldn't be a problem.

• #### Re:Sunny skies (Score:5, Informative)

<shawn-ds@willden.org> on Friday November 28, 2003 @12:50PM (#7582954) Homepage Journal

As long as he can design a solar plane which can fly at mach 2, this shouldn't be a problem.

Nahh, 700 mph is all he needs. If he flies with the sun, night will gain on him at a velocity of v_s - v, where v_s is the speed of the light's edge and v is his speed. If he takes off at dawn, and flies along the equator, he has to get all the way around (25,000 miles) before night, which starts out at 12,500 miles away, catches up.

So, he has to achieve a velocity v that satisfies both:

(v_s - v) t = c/2

and

v t = c

where t is the travel time and c is the circumference of the earth. Isolating t in each and setting them equal gives:

c / [ 2 (v_s - v) ] = c / v
==> 2 (v_s - v) = v
==> 2 v_s = 3 v
==> v = 2/3 v_s

Plugging in the numbers, that means he needs a velocity of about 694 mph, assuming the earth's circumference is 25000 miles.

• #### Re:Sunny skies (Score:2)

Doesn't that also assume that he's flying at an altitude of zero?
• #### Re:Sunny skies (Score:2)

No, only that the speeds listed are ground speeds :-)

Actually, it doesn't make much difference. For example, flying at 30,000 feet only adds 36 miles to the trip, which means he needs one additional mile per hour. Since we're already talking about speeds a good order of magnitude higher than what is likely to be achievable, it really makes no difference at all...

• #### RTFA Rant (Score:1)

He wants, by 2006, to have a through-the-night solar flight (36h). If he could do the circumnavigation in 24h, though, he could just avoid the night, and travel around the world at the same speed a day travels across the earth. Seems risky, if you suddenly hit problems over the pacific.

It's a long way to glide.
• #### Re:Sunny skies (Score:5, Informative)

on Friday November 28, 2003 @10:30AM (#7582168) Homepage Journal
You need to make 700mph to fly arround the world in complete sunlight, starting at sunrise on the equator, and taking 36 hours arriving at your departure point at sunset the next day.
• #### Oh no! RAIN! (Score:3, Funny)

on Friday November 28, 2003 @10:08AM (#7582036) Journal
Hope he stays above the clouds :-)

Simon
• #### no sun = no fly (Score:5, Funny)

on Friday November 28, 2003 @10:09AM (#7582040)
he'd better not fly over the UK then.. no sun here ;)
• #### OK... (Score:3, Funny)

on Friday November 28, 2003 @10:09AM (#7582044) Homepage Journal
Yeah, but does it run Linux?
• #### The grand grand grand grand grand son (Score:1)

Of Jean-Luc Picard? :-)
• #### Re:The grand grand grand grand grand son (Score:2, Insightful)

Given that TNG is set around 2380, wouldn't that be great great great great great great great great great great grand-father? :)
• #### You say Picard, I say Piccard, . . (Score:3, Informative)

Check out this dude here [centennialofflight.gov] and try and tell me the two aren't related.

Auguste Piccard was a Swiss while J-L Picard is a Scot actor playing a French dude. I am certain the Star Trek NG writers had in the back of their mind that A. Piccard was a famous explorer, and they wanted their J-L Picard to be more the Swiss Explorer than the Captain Cook-like J.T. Kirk. If they knew about A. Piccard, they may have changed the name and nationality to make it simpler for TV viewers.

Cook definitely was the inspiration

• #### Re:You say Picard, I say Piccard, . . (Score:2)

When Roddenberry was pitching the show to the networks, he said it was a "Horatio Hornblower in Space" type of show.
• #### Re:No, the son of Jacques & grand-son of Augus (Score:4, Informative)

<rduke15&gmail,com> on Friday November 28, 2003 @11:08AM (#7582334)
Who is Jean-Luc Piccard anyway?

Bertrand is the son of Jacques and the grand-son of Auguste. See his biography [bertrandpiccard.com].

"His grandfather, Auguste (1884-1962), [...invented] the principle of the pressurised cockpit and the stratospheric balloon. In making the first exploration of the stratosphere [...] in 1931, he [...] became the first man to see the curvature of the earth's surface with his own eyes."

"His father, Jacques, continued the work of Auguste [...] the world's deepest dive (-10916 metres in the Marianas Trench, the greatest known ocean depth)."

• #### solar polar (Score:1, Interesting)

by Anonymous Coward
how high would you need to fly at what lattitude and at what time of year to get out of earth shadow?
• #### Re:solar polar (Score:3, Interesting)

how high would you need to fly at what lattitude and at what time of year to get out of earth shadow?

Any trig gurus please improve this for me:

Let T = radius of the earth
Let L = given angle of latitutde
Let X = "altitude" above the center of the earth to escape the earth's shadow
Let A = altitude above the earth's surface.

Now assume it is an equinox (thus the sun's rays are tangent to the earth at the poles), we want to find:

A

A = X - T since radii of a circle are equal
X = T * sec(L) X is our hypote

• #### Re:solar polar (Score:1)

Whatever it is, it is going to be pretty darn high. The earth's atmopphere isn't very big, either. I don't know how to simplify (sec(L) - 1), but would if it was sec(L)^2
• #### Re:solar polar (Score:1)

You're thinking of tanx - secx = -1.
• #### Re:solar polar (Score:1)

tan^2(x)-sec^2(x) = -1, sorry, I forgot slashdot doesn't support special characters. My squared didn't work.
• #### Re:solar polar (Score:1)

well given that you can see earth's shadow on the moon, which is completely out of the atmosphere, i'd say its not very practical to consider this
• #### Why? (Score:1, Interesting)

by Anonymous Coward
Is there any scientific value to going around the world in a balloon, solar plane, or whatever? Or are these just things that wealthy people do to keep themselves occupied?
• #### A bit of both (Score:2, Insightful)

Is there any scientific value to going around the world in a balloon

Is there any scientific value to space exploration?

I'm guessing that circumnavigation of Earth in a particular class of vehicle acts as a sort of proof of concept to the vehicle's operation. Engineers at transportation industry companies usually want to work with ideas that somebody else has tested in the field, and this is where the wealthy people's pastimes come in.

• #### Re:Why? (Score:1)

Or are these just things that wealthy people do to keep themselves occupied?

What, you don't think that these people actually pay for the rescue mission to come get them when their bathtub sinks in the middle of the ocean, they get lost looking for Santa's workshop, or whatever.

They should be made to sign a "no extreme measures or rescue-tation attempts" paper before leaving.

• #### Re:Why? (Score:2, Funny)

• They should be made to sign a "no extreme measures or rescue-tation attempts" paper before leaving.
Right. I can't remember how often that guy had to be rescued with his balloon but i do remember that he needed a few tries and almost died more than once.

Any bets on how many tries it will take him this time?
To me, this is Jackass for rich people.
• #### Re:Why? (Score:2)

If it weren't for "crazy" people like this, we'd probably live in a very different world now. Consider for example Columbus, and then consider the entire "Great Voyages" that his example inspired. (Well, Asians and especially American Indians might disagree about that being a good thing...)

We've mostly run out of new places to explore without enormous cost of trying to do manned flights to other planets, so people like this are left with exploring the oceans and flying around the world in different contr
• #### Re:Why? (Score:2, Interesting)

Hey, I have no problem with people trying stunts that seem crazy at the time--and dying because maybe it was crazy.

What I object to are the people that do some damned-fool stunt like travelling to the north pole by pogo-stick, then calling for help when they get snow in their boot. Suddenly a huge effort to save them is made at great expense and risk to other people. Launching a search and rescue effort shouldn't like calling the AAA. If you want to do something dangerous, do it. Or do not and die.

• #### eco friendly? (Score:4, Interesting)

on Friday November 28, 2003 @10:14AM (#7582086) Journal
So after a few years of r&D half a dozen custom built protoypes (to be discarded as non-biodegradable junk) and other discarded parts they can have something that probably took more energy to make than a small town uses in a year, but then fly it around the world using only energy from the sun...I suppose it will be a cool engineering achievement.
• #### Re:eco friendly? (Score:3, Insightful)

Solar cells are not efficient, we all know that. We know that it takes more energy to build them than they will ever produce in their lifetime.

But hey, this can be improved and to improve it researchers need funds. For researchers to get funds they have to make people understand that it's possible and that beautiful things could be achieved with solar cells. That's one of the purposes of this project.

Anyway, I still prefer that guy building an expensive plane in terms of energy than millions of people rid
• #### Re:eco friendly? (Score:5, Insightful)

<wrewrite AT gmail DOT com> on Friday November 28, 2003 @10:46AM (#7582243) Journal
So after a few years of r&D half a dozen custom built protoypes (to be discarded as non-biodegradable junk) and other discarded parts they can have something that probably took more energy to make than a small town uses in a year, but then fly it around the world using only energy from the sun...

A Proof of Concept product is always more costly. You can think of R&D costs not concentrated in a single product, but amortized across the series of product lines inspired by the new engineering, whether those costs are money or calories or a balance of available resources. The long-term savings (in all economic senses) represented by efficient design suggests a real bargain for global society.

The publicity stunt aspect of this is really a kind of marketing for sustainable tech in the long view.

• #### Re:eco friendly? (Score:1, Redundant)

It's a proof of concept. If it succeeds, evolved versions of the technology could very well end up saving money/energy.
• #### Re:eco friendly? (Score:5, Insightful)

on Friday November 28, 2003 @11:00AM (#7582300)
Do you truly not see why developing solar energy technology to the level that makes this kind of plane possible is eco-friendly proejct, or are you just trying to troll?

And it's not just developing better solar cells to enhance current applications of solar energy.

Consider for example that if a lot of oribital satellites could be replaced with purely solar-powered autonomous planes that could stay up theoretically indefinitely. Just think how much "non-biodegradable junk" can this project produce to match the environmental impact of just a single space rocket launch...

Or imagine a hydrogen fuel-cell car that could partly refuel itself in a sunny parking lot during the workday, and could keep moving (slowly) even if you run out of fuel. Not much use in higher latitudes maybe, but imagine southern China, India and entire SE Asia with 2 billion cars like this instead of 2 billion cars using fossil fuels.
• #### Was Biosphere 2 junk science? (Score:2)

On the topic as to whether the solar plane is science or a stunt, some dude had a book on junk science where he included cold fusion and Biosphere 2 as junk science.

Now I am not trying to troll here as some of you may point to evidence for cold fusion. But Fleischmann and Pons certainly didn't help their cause by being sloppy with experimental control and calorimetry, so the way it played out it is fair to lable what happened as junk science.

I was suprised to see Biosphere 2 labled as junk science. No

• #### Power storage (Score:5, Insightful)

<geckofood AT gmail DOT com> on Friday November 28, 2003 @10:16AM (#7582098) Journal
So, assuming he has clear skies for most of that trip, no problem. However, if he hits "inclement weather," how much energy does that plane store up before it runs out of juice? Or can it be assumed he will be above the cloud cover for the whole trip? And, is it assumed the trip is continuous or will he be able to stop at "jump points" (this makes more sense for obvious reasons). If he can stop even briefly, this idea becomes a lot more feasible.
• #### Re:Power storage (Score:5, Interesting)

on Friday November 28, 2003 @10:26AM (#7582153) Homepage
I was wondering that too. I'd assume that the plane would essentially be a glider and would use the solar power to provide lift as required and thrust only if sufficient spare energy was available. I'd also assume any onboard batteries would be fully charged at takeoff too to give things a head start.

Even so, doing this in one hop seems a little unlikely, unless circumnavigation near the pole in summer is in order, and it's not in my book! Ignoring the tilt of the Earth, then taking off at dawn and flying west to maximise the amount of daylight would require a circumnavigation within 36 hours before night would fall. That's in the region of an average speed of 1,000mph. Fully charged batteries at takeoff, flying on battery through pre-dawn and recharging through the day and finishing off on battery at night would reduce that some, but enough for one hop?

• #### Re:Power storage (Score:4, Informative)

on Friday November 28, 2003 @10:36AM (#7582190) Homepage
Ah ha! Found the relevent paragraph of the website! They do indeed expect to stay aloft overnight, several in fact, which means enough power stored in batteries to keep the aircraft aloft during the shorter summer nights. I can't see any mention on whether they plan on gliding and using the propellers as required or not though.
• #### Re:Power storage (Score:2)

That's in the region of an average speed of 1,000mph.

Considerably less. The Earth has a circumfrance at the equator of slightly under 40,000km, While the course won't be a straight line, and will probably follow jet streams and avoid certain countries, it shouldn't be more then 50,000km, meaning an average speed of 860mph. If the course is a straight line then an average speed of just under 700mph will suffice.
• #### Re:Power storage (Score:4, Informative)

on Friday November 28, 2003 @10:28AM (#7582158)

An aircraft of this type will certainly be cruising above the clouds, and will be steering well clear of any convective activity (thunderstorms) for safety reasons. The real power storage challenge is to get through the night.

This is the reason you don't see all that many solar-powered UAVs, never mind piloted aircraft. The economics of solar flight would change radically if battery technology improved.
• #### Re:Power storage (Score:3, Informative)

By looking at the site it appears as if they would be doing it non-stop. The following is from their list of objectives:

# Complete night in the air during the first 36 hour solar flight in June 2007;
# First flight tests of the second prototype from end 2007;
# Solar flights lasting several days from start of 2009.

With a 36 hour solar flight in June 2007 and then a several day flight in 2009 (plus all of the other information actually on the site) it would seem like a safe assumption that they ar

• #### Easy (Score:3, Funny)

on Friday November 28, 2003 @10:16AM (#7582100)
All he needs is a really big bungee cord...
• #### Obligatory... (Score:3, Funny)

on Friday November 28, 2003 @10:17AM (#7582108)
Obliugatory Piccard joke.....

Piccard: To boldy go, where no ma- (turbulence) Number 1, why are we rapidly descending?

Riker: It seems to be a solar eclipse sir

Piccard: All hands embrace for impact!
• #### Re:Obligatory... (Score:3, Informative)

According to the wikipedia, Jean-luc Picard was named after Dr. Jean Piccard [wikipedia.org], another balloonist!

• #### Re:Obligatory... (Score:1)

According to the wikipedia, Jean-luc Picard was named after Dr. Jean Piccard, another balloonist!

Jean Piccard is also Betrand Piccard's grandfather.
• #### Re:Obligatory... (Score:2)

Jean Piccard is also Betrand Piccard's grandfather.

After furthur digging, I found that Bertrand is his grand-nephew. Jean was the twin brother of Auguste Piccard. Auguste's son was Jacques Piccard and Bertrand is Jacque's son. A whole generation of balloonist-adventurers! How cool is that?

• #### Re:Obligatory... (Score:2)

"Piccard: All hands embrace for impact!"

"Data: If we proceed at this velocity, the Enterprise will be destroyed."

"Picard: Troi, you have the conn."
• #### Glider (Score:5, Interesting)

on Friday November 28, 2003 @10:21AM (#7582124) Homepage Journal
People can stay in the air for several days in a glider. They use upward currents to gain height. You know, fly over a desert in the day, and over a forest at night.
• #### Get off the cross (Score:5, Insightful)

on Friday November 28, 2003 @10:24AM (#7582146)
We need the wood.

Spare me the "any mention of ecology gets a lukewarm response from the public because their comfortable existence is threatened".

The problem with many so-called 'ecologists' is that they frame everything in terms of 'saving the Planet'. Here's a clue - the Planet will survive long after we're all dead. The Earth will be there when the sun becomes a red giant and eats it. We shouldn't save the Planet, we should save ourselves. Does the Earth 'care' if biodiversity diminishes due to pollution? Does the Earth 'care' if the light pollution causes algae disruptions in the Great Lakes? No. but we should.

This project is great at raising visibility and research focus in the fields of energy capture, storage and motor design, but these folks aren't the Messaihs.
• #### Re:Get off the cross (Score:2, Insightful)

I bet we could exterminate most nn-human life if we really tried. Or if we let factories spew out pollution at any rate they please (which would be a cheaper way to do it). How would you like to breathe smog, instead of air? Granted, though, the *planet* won't die, but what we care about are living things.
• #### We're not alone... (Score:5, Insightful)

on Friday November 28, 2003 @10:54AM (#7582276) Journal
Perhaps we have a right to wipe humanity of the face of the planet, perhaps we don't. But I don't see how we have a right to wipe out all the countless other species and to poison the earth, sky and the seas.

To use a famous quote, this is a beautiful planet, it's a miracle and we're destroying it.

(Cue a dozen posts from people who think environmental awareness is for only for hippies high as a kite.)
• #### Re:We're not alone... (Score:1)

No, it's ok. After we destory humanity, apes will rule the planet [imdb.com]. Really.
• #### Re:We're not alone... (Score:1)

But I don't see how we have a right to wipe out all the countless other species and to poison the earth, sky and the seas.

Fine, you're more normal than us-what do you want, a paper hat?
• #### Re:We're not alone... (Score:2)

Sounds like tinfoil would be more appropriate.
• #### Re:We're not alone... (Score:3, Insightful)

by Anonymous Coward
We aren't going to "wipe out all the countless other species" out there. I seriously doubt we could do it, even if we tried, at this point.

We'll kill some, but we'll also create new environmental niches for other species to evolve to fill. The various rodents, and pets, and farm animals that have evolved and prospered in symbiosis with man may not be "exotic" enough to satisfy those high as a kite hippies you mentioned, but they are no less alive or a part of this world's environment.

What one being sees
• #### Re:We're not alone... (Score:2)

I think the point of the parent and many others is that the niche you are describing will not include mankind. That is perhaps the best argument against wonton destruction of the environment. Humankind can easily paint itself into a corner if it doesn't protect the habitat in which we flourished as well as other species.
• #### Re:Get off the cross (Score:3, Interesting)

The problem with many so-called 'ecologists' is that they frame everything in terms of 'saving the Planet'.

No, the problem with many so-called ecologists is that they frame everything in terms of threats to 'our comfortable existence'. They wrongly believe that it 'has to hurt if it's to heal', and translate every ecological problem, not just global warming but local small scale problems as well, into something that can, will and should have an enormous impact on our everyday lives. They do not believe

• #### Re:Get off the cross (Score:1)

Interesting that the most liberal would share a common trait with the most conservative, the idea that "if it feels good, it must be bad".
• #### Re:Get off the cross (Score:2, Insightful)

by Anonymous Coward
Don't be so literal.

Save the planet means save the lifeforms on the planet; save the beauty of the planet; keep it all the same so our grandkids can enjoy a walk on the beach and a trip through the woods.

Not saving the planet is trashing it in small ways by throwing a soda can down in a forest or large ways by nations using the oceans as a sewer.

Not saving the planet is letting lots of species die out - faster than evolution can replace them.

New York trash including needles washed up on New Jersey beach
• #### You first (Score:2)

Save the planet means .. keep it all the same ...

You lose. Nothing stays the same.

So help save the planet and be a hero!

You first. You could start by not reproducing, and killing yourself, because you're using stuff up. The basic problem here is that there are TOO DAMN MANY PEOPLE. Stop sweating the small stuff and address the underlying problem.

Not saving the planet is letting lots of species die out - faster than evolution can replace them.

"Lots" is kind of vague, but I don't have a knee jer
• #### Re:You first (Score:1)

The basic problem here is that there are TOO DAMN MANY PEOPLE. Stop sweating the small stuff and address the underlying problem.

Don't worry, AIDS in on its way.
• #### Re:Get off the cross (Score:3, Insightful)

Here's a clue - the Planet will survive long after we're all dead. The Earth will be there when the sun becomes a red giant and eats it. We shouldn't save the Planet, we should save ourselves. Does the Earth 'care' if biodiversity diminishes due to pollution? Does the Earth 'care' if the light pollution causes algae disruptions in the Great Lakes? No. but we should.

That's a very humanistic position, which suggests that homo sapiens' mental capabilities separate us from the rest of the planet. You're sayin

• #### Re:Get off the cross (Score:2)

That's a very humanistic position, which suggests that homo sapiens' mental capabilities...

Excellent post! You took the parent's point and drove it home with a 25-lb sledge. It's exactly that sort of claptrap that makes the public yawn when environmental issues are raised.

• #### Re:Get off the cross (Score:1)

Yeah, let's invent the matrix. Then, who cares about the Planet as long as virtual reality satisfies our mind and the machines satify our body needs.

And we are a lot better than all those plants and animals. As long as we survive, who cares about those pesky things.
• #### Re:Get off the cross (Score:2)

It's a fine distinction IMHO.

If I asked you to "save me a seat," would I be implying that all the seats were about to be destroyed? To most people I think "saving the planet" just means keeping the air and water clean etc. so we can live here comfortably.

Sure there are a few kooks advocating human extinction so the planet can live for its own sake but nobody is listening to them.

• #### Everyone asking 'can it fly at night' (Score:5, Informative)

on Friday November 28, 2003 @10:25AM (#7582151)

If you had clicked the article link, you'd see a picture of it flying at dusk, right on the front page!.

Also from the press release [solar-impulse.com]

The Solar Impulse aircraft will have an extremely long wingspan, advanced aerodynamics, and a revolutionary structure in order to capture and store sufficient solar energy during the day and to be able to maintain itself in flight during the night.
• #### Re:Everyone asking 'can it fly at night' (Score:5, Interesting)

on Friday November 28, 2003 @10:55AM (#7582282)
My guess is that they will probably climb during the day and charge batteries then glide all night with a small power draw to the batteries extending the glide. If they can climb enough during the day then they might not need to use batteries, and just glide until the morning. It should be possible to build such a machine with less than 100ft/min sink rate, perhaps even 50ft/min. Thanks 3000-6000 ft lost per hour, 8 hours is 24000-48000ft height loss. Manned flight makes this more complicated though with needing oxygen and heating the pilot at high altitudes.
• #### Re:Everyone asking 'can it fly at night' (Score:2)

Another observation; assuming you are heading West, which seems more logical to me, then the faster you fly during the day (under solar power) the longer time you have in daylight. At night though, it may be better to fly *slower* so that the sun catches up with you faster and you can regain solar power sooner. You could even *backtrack*, flying back East on battery to help shorten the periods of darkness!
• #### not going to happen??? (Score:3, Funny)

by Anonymous Coward on Friday November 28, 2003 @10:28AM (#7582160)
and you run and you run to catch up with the sun but its sinking, only to come up behind you again...
• #### Flying backwards to meet the dawn (Score:4, Interesting)

on Friday November 28, 2003 @10:35AM (#7582185)
I would assume that the pilot would fly a zigziag course. During the day, they would fly westward to stay in the sun as long as possible. During the night, they would fly eastward to meet the dawn as soon as possible.

I also wonder if they might choose a route that flies over the upwelling of air at the equatorial convergence zone. It might be rough, but those air currents could help them stay aloft during the night.
• #### Re:Flying backwards to meet the dawn (Score:2, Funny)

by Anonymous Coward
Bob: "How come we're not getting anywhere?"
Phil: "Cos the flight plan has us doing a one-eighty every sunrise and sunset."
Bob: "Oh?"
Phil: "Yeah, more cold coffee please."
• #### That's not cool (Score:4, Funny)

by Anonymous Coward on Friday November 28, 2003 @10:41AM (#7582217)
They should go around the world in a solar-powered submarine.
• #### here's the science bit (Score:1, Informative)

by Anonymous Coward
well ive already mentioned the factors involved in earth shadow. now we must consider the energy requirements and aerodynamics.

solar energy 1.4KW m^2 outside earth atmosphere.

atmospheric radiation dissipation due to various phenomena in clear sky conditions below tropopause 0.11KW/KM

so we should have 03KWm^2 of top surface area.

we can throw in some basic guestimates that the wing area will be ~= 20m^2. a moderate flying speed of around 200knots. and NACA aerofoil efficiency of around 0.83.

now taking th
• #### Remember Helios? (Score:5, Interesting)

on Friday November 28, 2003 @11:07AM (#7582327)
NASA's little darling solar plane flew at about 90,000 feet, well above any potential cloud cover. You can assume that these guys are planning on the same strategy. But if you plan to send a manned flight up to 90k feet, doesn't that raise a whole slew of logistics questions? i.e., the amount of oxygen needed, the weight ratios to follow, etc...
• #### I can just imagine the TV ads for this... (Score:2, Funny)

soundtrack: "don't let the sun go down on me" by Elton John
• #### Paul MacCready (Score:4, Informative)

on Friday November 28, 2003 @11:32AM (#7582494)

Those interested in efficient flight should read about Paul MacCready (and many others) who have been involved in the American human/solar powered flight movement: More with Less: Paul MacCready and the Dream of Efficient Flight [amazon.com].

• #### A better link, explaining the technology (Score:4, Informative)

<rduke15&gmail,com> on Friday November 28, 2003 @11:34AM (#7582507)
The EPFL explains much more about the technological aspects. It's in French of course: here [www.epfl.ch].

But for those who cannot read :-), they also have nice pictures [images-sol...se.epfl.ch]

One technological aspect is that by flying very high, they can take advantage of the cold (-55C), which can improve efficiency of electro-magnetic motors.

There are other interesting bits. I guess the page will be translated in English in a few days. (Forget computer translations, unless you want a cheap laugh)
• #### Consumables are the problem (Score:3, Informative)

on Friday November 28, 2003 @12:06PM (#7582644)
The Helios Solar Airplane [pvresources.com] probably could have flown around the world. But with a cruising speed of only about 40 km/hr it would have taken 1000 hours (41 days). Such a long duration flight is fine for an unmanned aircraft, but poses severe challenges for manned flight. Carrying weeks worth of food, water, and oxygen represents additional payload that such a vehicle can ill afford. Onboard recycling/extraction systems could reduce the need for consumables, but they add weight also.

But without a person in the cockpit, the venture won't get much media attention. And without media attention, the project won't attract much sponsorship. ..... SIGH!
• #### Re:The person in the cockpit (Score:2, Interesting)

But without a person in the cockpit, the venture won't get much media attention. And without media attention, the project won't attract much sponsorship. ..... SIGH!

Exactly.

And being the "person in the cockpit", and attracting sponsorship is what the latest Piccard seems to be good at.

And he is nicely grateful to his sponsors too. On the contacts page [solar-impulse.com] of the site, the link to his own site (www.bertrandpiccard.com) actually points to his sponsors (www.breitling.com)! Whether it is accidental, intentional
• #### Consequences of using solar power? (Score:2, Funny)

Right now, using solar power sounds like a good idea. It's a renewable and non polluting source of energy.

But if we have learned anything about excessive energy use from the past, we should proceed with caution. What will happen when the whole world is powered by solar power? Think of it, all this energy from the sun that would normally heat the earth would now go towards generating electricity. This would probably lead to a global chilling which is not a good thing.

I think we should either stay dependant

• #### Re:Consequences of using solar power? (Score:1)

But if we have learned anything about excessive energy use from the past, we should proceed with caution. What will happen when the whole world is powered by solar power? Think of it, all this energy from the sun that would normally heat the earth would now go towards generating electricity. This would probably lead to a global chilling which is not a good thing.

No. The solar generated elecricity will ultimately turn to heat. Unless people decide to store large amounts of it, it will be used and conve
• #### Thank Burt Rutan for this; (Score:2, Interesting)

December 1986 this was done with fuel [centennialofflight.gov]
Why can't this now be done with solar cells and high-density batteries?

I would have more faith in this project if it was being done by somebody else.

Stay aloft for weeks at a time? sure why not. Just expand on this idea [air-attack.com]
• #### The other balloon guy (Score:2)

Remember the other famous balloon guy: Steve Fossett (millionaire with to much spare time, first solo balloon flight around the world [slashdot.org]). He is also playing with gliders these days. A year ago he tried to achieve a new height by soaring a mountain wave [slashdot.org] (but didn't succeed?). Right now he seems be persuing [fossettchallenge.com] some other gliding records and building some big boats.

Having done some gliding myself (~50 solo flights, never got my licence though) i think this is really cool.
• #### Awareness my Ass (Score:5, Insightful)

on Friday November 28, 2003 @12:52PM (#7582973)

Just repeat after me:

I have a 2kw solar system on my roof so I'm certainly not anti-renewable energy. I just think people should realize that the problem has nothing to do with technology or people's desire maintain their lifestyle because it's not even allowed to come down to that. It's about greed and established infrastructure. I don't think it's any coincidence that the major solar panel manufacturers are all owned by oil companies. I can't prove it but it doesn't seem unreasonable to assume that they are controlling the price of solar panels to keep the usage at a level that is comfortable to them.

We have reached the level of corporate control in this world that is reminicent of the movie Rollerball (for those of you old enough to remember it). The U.S. courts and the EU and make a good show of protecting their citizens but corporations don't need to do anything illegal to get what they want. With enough money and lawyers you can blunt any reform that comes down the pike. Movies have to be more dramatic but the truth is much more banal.

I'm glad Mr. Piccard has the ability to put together these inspiring projects. I wish he'd invite me to be on his team. I just don't think for a minute that it's going to address the real problem.

"I tried solar power but it just made my skin peel. I'll stick with food, thank you."

• #### Re:Awareness my Ass (Score:2)

You are correct in everything but the movie!

Regarding Piccard's project...Many people don't understand how diffuse energy can be used effectivly, this could be a way to educate people. Not that it is a way I'd choose mind you, but it is possible.

• #### solar cells on the back of the wing (Score:2)

I woder if the plane has solar cells on the ground facing part of the wing. Extra sunlight reflected from clouds is always a bonus.
• #### Forget solar (Score:3, Funny)

on Friday November 28, 2003 @03:48PM (#7583870)
after reading the website, it's clear to me that if Piccard were to make an ego powered craft he could probably land on the Moon.

I have a very small mind and must live with it. -- E. Dijkstra

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